An automated cutting chamber hood and larger dimensions enable the Krupp Werner & Pfleiderer UG 700 underwater pelletizer to produce up to 50 metric tons of plastic pellets per hour.

The new pelletizers are larger than their predecessors. Measuring 3.9 by 1.6 by 2.5 meters, they are equipped with up to 36 knives. The 200-kilowatt machine circulates 650 cubic meters of water to achieve high output. Process water is then supplied and removed tangentially near the pelletizing die to improve flow conditions and part quality while minimizing the buildup of contaminants in the water.

The hydraulic cylinders used to open and lock the UG 700 cutting chamber hood are automated to prevent operator error during startup, and the entire pelletizer is monitored and operated by a central control system. These automated features provide a smooth, reproducible startup within a specified time period and reduce the number of startup personnel required. In addition, the locking points of the hood are defined and clamped evenly to eliminate knife damage. The safety equipment monitors the danger zone of the pelletizer to protect personnel from mishaps.

Sparing the pelletizer's knives and die from wear was another consideration for the UG 700 design team. To that end, they provided the rotor bearing with an automatic double-action feed ar-rangement to reduce stresses on the knives. During operation, when the knives reach a predetermined peripheral speed, they create a vacuum that combines with the set knife infeed contact pressure to push the cutting blades against the pelletizer die. This enables the operator to reduce the infeed pressure until the load on the knives is removed, thus minimizing knife and die wear while maintaining sufficient contact force to cut the pellets.

Dectron dehumidifiers condense enough water in one year to fill the 10,000-square-foot pool in the aquatic theater of the Bellagio Hotel in Las Vegas, where the famed Cirque du Soleil performs.

A key challenge for Dupras engineers was designing the proper sizing of HVAC equipment to accommodate humidity variances presented not only by the huge pool surface, but also by the many water jets that shoot streams up to 60 feet high and a giant mist curtain used in laser light shows. Among the considerations was a 112-by-65-foot decorative glass dome that towers above the 82-foot-high room and must be kept free of condensation.

Project engineers Andre Dupras and Luc Fontin designed an air distribution system to keep the space free of drafts or ventilation noise. This system consists of 300 swivel nozzle jet outlets installed over the pool and stage areas, 159 4-by-24-inch diffusers mounted at the bottom of perimeter walls, and 1,350 six-inch-round diffusers, each placed under a spectator's seat.

The entire system keeps air and water temperatures at a constant 82°F and 84°F, respectively, while controlling humidity by the installation of four Dry-O-Tron DS-242 dehumidifiers made by Dectron Inc. of Roswell, Ga. Two dehumidifiers are on each side of the pool. Each unit removes up to 1,050 pounds of moisture every hour by means of a HyPoxy-coated aluminum-finned evaporator coil. A fifth Dry-O-Tron DS-60 dehumidifier dries out the air around a practice and warmup pool backstage. An additional benefit of the dehumidification of the Bellagio's aquatic theater is that the condensation collected by the dehumidifiers is drained and recycled into the pool. Over the course of a year, recycling reclaims sufficient water to fill the entire pool, an economic plus in arid Nevada.

Swanson is internationally recognized as an authority and pioneer in the application of finite-element methods to engineering. In founding ANSYS in 1970, Swanson foresaw the development of the computer as a replacement for the engineer's handbook, diagnostic tools, and manual calculations, so that all design, testing, and manufacturing would originate in the computer. According to Swanson's vision, engineers would be able to use the computer to predict the effects of stress, temperature, pressure, and motion on a design, instead of investing in expensive prototypes and testing. By making his easily integrated general-purpose program widely available, he has given engineering analysts and design engineers a central tool to accelerate design cycles, hasten product time to market, reduce design and production costs, improve engineering processes, and promote product quality and safety.

The ANSYS analysis code has been applied to products in such wide-ranging industries as consumer goods, electronics packaging, industrial equipment, and biomedicine. Today, the company focuses on helping customers meet engineering challenges and compete in a global marketplace. ANSYS Inc. was the first finite-element design and analysis software developer to obtain ISO 9001 certification. The current ANSYS product line features open, flexible architecture that permits easy integration into its customers' enterprise-wide engineering systems, as well as state-of-the-art CAD integrated products.

"I am honored to receive this. I am really accepting this award for the large group of people who have been behind the ANSYS program during the last 30 years," said Swanson. Swanson was named 1986-87 ASME Pittsburgh Engineer of the Year and was elected an ASME Fellow in 1994. Prior to founding ANSYS, Swanson worked at Westinghouse Astronuclear Laboratory in the stress analysis group in reactor design, the core analysis and methods group, and the structural analysis group. He holds a B.S. and M.S. in mechanical engineering from Cornell University, and a Ph.D. in applied mechanics from the University of Pittsburgh.

Bank One Ballpark in Phoenix, home of the Arizona Diamondbacks, has a network infrastructure that combines communications and technology information systems into one cabling pathway. This intelligent solution provides the National League's latest expansion team with a facility designed to integrate voice, video, and information technologies.

The companies that developed the infrastructure are Lucent Technologies in Murray Hill., N.J.; Andover Controls in Andover, Mass.; and Vicon Industries in Hauppauge, N.Y. Lucent's Systimax system, originally developed by Bell Laboratories, serves as the fiber-optic backbone network through which all systems are integrated. Andover's Infinity system provides approximately 7,500 control points that operate several specialized systems including heating, ventilation, and air conditioning; security; lighting; fire alarms; cable television; and the retractable dome roof. Vicon supplied the video communication capability, including video surveillance domes and digital video multiplexers. Phoenix-based ATT Integrated Technologies was the certified installer for the Andover and Vicon products.

The network not only manages the ballpark's building management and communication systems but also provides a technology platform for radio and television broadcasts, electronic scoreboards, in-stadium monitors, and up-to-the-minute player statistics.

The process is called polymer micro-encapsulation and is designed to reduce the leaking of contaminants into the environment to very low levels from waste in a landfill. The technique involves converting waste into a powder by drying or shredding. The powder is then poured into an extruder or a kinetic mixer, where it is mixed with molten polyethylene. A third ingredient is sometimes added to bind up radioactive elements and toxic chemicals in the waste. The resulting mixture is fed into a 55-gallon drum, where it cools and hardens into a solid, monolithic form, completely surrounding waste particles in non-biodegradable plastic.

The plastic protects the waste from chemical reactions with air or water, including rain and floods, which can lead to the migration of contaminants, said Paul Kalb, a mechanical and nuclear engineer at Brookhaven National Laboratory and one of the inventors of polymer microencapsulation. This process can be used on virtually any form of waste, including incinerator ash, sludge, and concentrated liquid. An advantage of using polyethylene instead of other materials to contain mixed waste, such as concrete, is that the plastic doesn't require a chemical reaction to harden. Chemical interaction with the waste could reduce product quality, performance, and durability, according to Kalb. The extruder unit at Envirocare processes one ton of waste per hour, while the kinetic unit treats two tons per hour.

PEMEX, the state-owned Mexican oil company, is using 18 mobile wastewater trailer units made by United States Filter Corp. of Palm Desert, Calif., to treat process water generated by the PEMEX refinery in Salamanca, Mexico. The system treats up to 1,200 gallons of wastewater per minute, enabling PEMEX to recover 70 percent for reuse in a region of Mexico where water is scarce.

SIPA Industrial Systems Division in Vittorio Veneto, Italy, will use the RobotWorld planar motion multihead automation systems developed by West Carrollton, Ohio-based Motoman Inc. SIPA incorporates Motoman's concurrent planar motor technology into its load/unload systems to attain up to 10,000 units per hour throughput.

General Electric Power Systems in Schenectady, N.Y., will supply equipment, training, technical assistance, operation, and maintenance services worth more than $275 million for a 700-megawatt independent power plant being constructed in the Ratchaburi Province in Thailand. GE will supply a STAG 209FA combined-cycle system, consisting of two MS9001FA gas-turbine generators and one large steam-turbine generator for the plant, which is scheduled to begin commercial operation by mid-2000.

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